The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 29, 2020
Filed:
Nov. 08, 2018
Applicant:
Enhanced Drilling A.s., Straume, NO;
Inventor:
Børre Fossli, Oslo, NO;
Assignee:
Enhanced Drilling, AS, Straume, NO;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21B 21/00 (2006.01); E21B 43/38 (2006.01); E21B 21/08 (2006.01); E21B 47/047 (2012.01);
U.S. Cl.
CPC ...
E21B 21/001 (2013.01); E21B 21/003 (2013.01); E21B 21/08 (2013.01); E21B 43/38 (2013.01); E21B 47/047 (2020.05); E21B 21/085 (2020.05);
Abstract
A subsea drilling method for controlling the bottom hole annular pressure and downward injection rate during mud cap drilling operations from a mobile offshore drilling unit with a low pressure marine riser and subsea blowout preventer. The method called controlled mud cap drilling uses the hydrostatic head of a heavy annular mud (fluid) managed or observed in order to balance the highest pore pressure in the well and to control the injection rate, by using a subsea mud lift pump and a control system to regulate the process.